PNAS:古代人族的DNA序列

德国马克斯•普朗克进化人类学研究所科研人员报告了两个丹尼索瓦人族标本的DNA序列。2010年，在西伯利亚丹尼索瓦洞穴中发现的丹尼索瓦3号标本指骨的细胞核基因组序列将这个骨鉴定为属于有别于尼安德特人和现代人的一个此前未知的人族群体，称为丹尼索瓦人。还在丹尼索瓦洞穴中发现了两枚推定的丹尼索瓦人臼齿——丹尼索瓦4号和丹尼索瓦8号。Svante Pääbo及其同事对来自这些臼齿的细胞核DNA以及线粒体DNA(mtDNA)进行了测序。这些丹尼索瓦臼齿比尼安德特人或早期现代人的臼齿更大，而且缺乏尼安德特人或早期现代人的臼齿的典型特征。对细胞核DNA序列的分析提示，所有这3个标本属于同一个系统发生群体，并且支持了一种观念，即这个群体有别于尼安德特人和现代人。这组作者使用来自这3个丹尼索瓦人标本的线粒体DNA推断了他们的相对年龄。丹尼索瓦8号的线粒体DNA比丹尼索瓦3号或4号的线粒体DNA积累的突变更少，这提示丹尼索瓦8号比其他两个标本显著更古老。这组作者说，丹尼索瓦8号与其他两个标本的年龄的差异提示，丹尼索瓦人在丹尼索瓦洞穴附近的区域生活了一个长的时期。。

原文链接：

Nuclear and mitochondrial DNA sequences from two Denisovan individuals

原文摘要：

Denisovans, a sister group of Neandertals, have been described on the basis of a nuclear genome sequence from a finger phalanx (Denisova 3) found in Denisova Cave in the Altai Mountains. The only other Denisovan specimen described to date is a molar (Denisova 4) found at the same site. This tooth carries a mtDNA sequence similar to that of Denisova 3. Here we present nuclear DNA sequences from Denisova 4and a morphological description, as well as mitochondrial and nuclear DNA sequence data, from another molar (Denisova 8) found in Denisova Cave in 2010. This new molar is similar to Denisova 4 in being very large and lacking traits typical of Neandertals and modern humans. Nuclear DNA sequences from the two molars form a clade with Denisova 3. The mtDNA of Denisova 8 is more diverged and has accumulated fewer substitutions than the mtDNAs of the other two specimens, suggesting Denisovans were present in the region over an extended period. The nuclear DNA sequence diversity among the three Denisovans is comparable to that among six Neandertals, but lower than that among present-day humans.

doi: 10.1073/PNAS.1519905112

作者：Susanna Sawyer